Under the condition of a large variation Tm in motor torque demand Tm*,
the significant torque change may lead to some vibration of a vehicle to
temporarily heighten an angular acceleration. The temporary rise of the
angular acceleration may cause the angular acceleration to exceed a
preset threshold value slip and result in misdetection of the occurrence
of a `phantom` skid in an angular acceleration--based skid state
determination (step S112). The drive control of the invention accordingly
specifies a potential for misdetection of the occurrence of a `phantom`
skid when the variation Tm in motor torque demand Tm* exceeds a preset
threshold value Tthr at step S108. The drive control thereby does not
execute skid occurring state control (step S120) with torque restriction
but performs grip state control at step S116.